Obesity and obesity related diseases are a significant health problem. Obesity is an excess proportion of total body fat. A person is considered obese when his or her weight is 20% or more above normal weight. About 39 million Americans currently fall into that category—an all-time high as of 2002. The cost of treating obesity and obesity-related diseases in America accounts for $238 billion, or approximately 20% of the nation's total health care bill, according to the American Obesity Association.
Substantial excess body fat may cause serious health problems. Extra pounds put great strain on the cardiovascular system, contributing to high blood pressure and heart disease, while high fat concentrations can enlarge the liver. Obesity also increases the risk of colorectal cancer.
An additional obesity related illness is adult onset, or Type 2 diabetes. Excessive weight gain may trigger Type 2 diabetes, in which body tissues become resistant to insulin produced by the pancreas. About 80 percent of people with Type 2 diabetes are obese. As a consequence of its microvascular pathology, diabetes is a leading cause of blindness, end-stage renal disease and a variety of debilitating neuropathies. Diabetes is also associated with accelerated atherosclerotic macrovascular disease affecting arteries that supply the heart, brain and lower extremities. As a result, patients with diabetes have a much higher risk of myocardial infarction, stroke and limb amputation.
The exact cause of obesity is still unknown. In addition, the exact causal link between obesity and obesity related illnesses are unknown. Research aimed at determining the cause of obesity and the link with related illnesses has been unsuccessful.
What is needed is a better understanding of the molecular biology and genetics surrounding obesity.